D Lamberet

Replaced battery and alternator. got full tank of gas. The DIC says low fuel. The fuel guage is at full. I know it is full as I just filled it up. Do I have to go to the stealership to get it reset? Any advice
danny

D Lamberet

Nobody has any experiance on this topic. Low fuel warning in DIC guage is at full???

BrianG01

was it an aftermarket/store brand alternator?

I hear that if it is anything but OEM it can cause all sorts of subtle electrical issues. It has been talked about some on the forum and maybe a search could help.

D Lamberet

nope factory Chevy alternator. 528.00 from local dealer. Thank god I realized I have GMPP. Stopped in service they filed a claim and refunded my money to me.

BrianG01

In that case It could be another common problem with the mechanism that detects the gas level. Run some fuel system cleaner, as it sometimes helps. I hear it is a pricey fix if that does not work.

'00FRC

I heard that specific years have a fuel gauge recall. I know you said that the gauge is reading full but if it is defective it could possibly account of the DIC to say low fuel. Not sure if this helps but check to see if the recall was done.

FLACHUSNRET

You should only use top tier gasoline in these cars. Chevron Supreme is usually recognized as the best gasoline for these cars and is all I put in mine unless I can't find it.
Get some Techron (about $6/bottle) and put in before fill up. It should clean up your fuel sensors in your gas tank.
If problem continues you should take it back to dealer and have them replace both fuel sensors in the gas tanks. This is about a $500 plus job which should be covered by your GMPP. There are new and improved parts for this job. Do not let the dealer install the old part number 10310028 left & 10310103 right side.
The new part numbers are 88967315 left and 88967316 right side. These new parts have a new ink coating that protects the sensors from the fuel contamination that is causing your problem.
Good luck with finding a fix!

alini

Run the diagnostics through the DIC and see what codes you get. The PCM takes signals from both tanks and adds them together to read the gauge and then after such a level in either tank it will flag as low fuel, sounds like a section of the sensor has gone bad....typical for 5th gens.
You can try to Fuel additive trick (run a bottle through the next few tanks) and or clean the contacts of your grounds. I did mine and the car is so much smoother running now.
info note the Fuel sensor system grounds through G401 which is in the left rear wheel well. Since you changed the battery, check the ground located next to it too.

Nyvetteguy007

As "they" say...keep it simple....

Try a bottle or two of Techron, that should clear it right up...use the bottles that treat 20 gal, not the 12 gal ones....I use Techron now every 2-3 tanks (since my gage dropped to empty)....dont have any issues (and prob the cleanest fuel tank nad injectors in town)...

Good luck...

trussme

...I've been doing this since my first episode with same problem. It worked for me ...no more low fuel codes. HERE's a GOOD TIP: " this usually occurs in the primary tank's (of the 2 you have) sending unit...because it emptys out 1st. and the dry sending unit will stick with the additive residue left from some fuels...So, start filling up right before the half full mark & add your TECHRON ,every 2nd or third fill up"........

D Lamberet

Thanks to everyone for input. I will work during the week. I hope the additive does it.

lookin4C3

I had a similar problem on my 98 tonite (first real cruise after purchase!!). Tanks were full, out of nowhere the guage drops to zero and I get a tank empty message!! I was pissed, but I pulled over, shut the car off for a minute and back on and everything was OK again.

Will definitely try the Techron trick!!!


Thanks, Andy

MIKER

Interesting. Of all the reading about fuel gauge/sending unit problems on the forum, this is the first time I've heard of the DIC saying "low fuel" while the gauge shows full. Interesting!
Has anyone else had the same symptoms?


I guess you are calling the right tank the "primary tank"? I don't know if the right tank is considered as the "primary" tank or not but It is the one which empties first. I can certainly see how the sensor can get fouled from drying out multiple times.

Nyvetteguy007

Whenever I have expereinced my issues with the fuel gage (no issues since using techron) it was accompanied by the "low fuel" display on the DIC...

Blue666's

I had the exact same problem with my 2000 Vert, and the gas guage would drop to empty along with a 'check guages' light on the instruments. Took it to the dealer and they found a bad right tank and sender unit. (Covered under my GMPP) Just got my car back yesterday and it's working fine. Pricey fix though, as they have to drop the rear end out of it to access/remove the tanks. I think the bill would have been around $2300 if not for the warranty coverage. I had to pay the $50 deductible, but that was it. Thank goodness the previous owner had this coverage, and I transferred it over to me. But I've often read on here that the Techron or Seafoam additive might cure the problem, if it isn't too severe. My service advisor said they see this problem periodically, expecially on 97-2001 models, the earlier the model the more frequently they see it. Just an FYI

MIKER

WOW! That certainly gives me more incentive to repair anything I can at home vs. taking it to the dealership. Thanks for the info.

jmaal13

Just had this problem last night. I bought the techron but i am not sure if I can put it in since i put 40$ in the tank before it happened. Do i have to run all the gas out?

Nyvetteguy007

In order for it to reach both sending units in both tanks you should have it as close to empty as possible.

I have done it with 1/4 tank and its worked.

MIKER

No, you do not have to run the gas out. Go ahead and pour the Techron in. The fuel within your two tanks is constantly being mixed while the fuel pump is running.

jmaal13

I drove it from the time i last posted until 7pm to only get the gas to 1/4. At that time i just couldnt take it anymore. Filled the car with gas and techron, started it and it only showed half a tank. After driving a minute it showed full. Still on the first techron tank, and i drove it again later in the evening and the low fuel gauge came on again. After driving a bit it came back on its own. After i run this first tank out, I will put another bottle of techron on the next fill up. After that I hope I dont see the problem again.